As we were walking along a street just off the western end of Chandni Chowk, we noticed a couple of youths following us. They managed to slip in between us in the crowd, and I saw one of them try to put his hand into my partner's pocket. Luckily there was nothing there!
Do be careful walking around the more touristy areas, and don't carry anything important in easily accessible pockets. Moneybelts worn under your clothes are obviously your best bet.
Be alert and don't believe strangers.As in any other country there are people who are good and bad. Beware of PicPocketers. If you are active then you are safe.